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-rw-r--r--drivers/scsi/mac_esp.c448
1 files changed, 448 insertions, 0 deletions
diff --git a/drivers/scsi/mac_esp.c b/drivers/scsi/mac_esp.c
new file mode 100644
index 000000000..6d23ab5ae
--- /dev/null
+++ b/drivers/scsi/mac_esp.c
@@ -0,0 +1,448 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* mac_esp.c: ESP front-end for Macintosh Quadra systems.
+ *
+ * Adapted from jazz_esp.c and the old mac_esp.c.
+ *
+ * The pseudo DMA algorithm is based on the one used in NetBSD.
+ * See sys/arch/mac68k/obio/esp.c for some background information.
+ *
+ * Copyright (C) 2007-2008 Finn Thain
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/nubus.h>
+#include <linux/slab.h>
+
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <asm/macints.h>
+#include <asm/macintosh.h>
+#include <asm/mac_via.h>
+
+#include <scsi/scsi_host.h>
+
+#include "esp_scsi.h"
+
+#define DRV_MODULE_NAME "mac_esp"
+#define PFX DRV_MODULE_NAME ": "
+#define DRV_VERSION "1.000"
+#define DRV_MODULE_RELDATE "Sept 15, 2007"
+
+#define MAC_ESP_IO_BASE 0x50F00000
+#define MAC_ESP_REGS_QUADRA (MAC_ESP_IO_BASE + 0x10000)
+#define MAC_ESP_REGS_QUADRA2 (MAC_ESP_IO_BASE + 0xF000)
+#define MAC_ESP_REGS_QUADRA3 (MAC_ESP_IO_BASE + 0x18000)
+#define MAC_ESP_REGS_SPACING 0x402
+#define MAC_ESP_PDMA_REG 0xF9800024
+#define MAC_ESP_PDMA_REG_SPACING 0x4
+#define MAC_ESP_PDMA_IO_OFFSET 0x100
+
+#define esp_read8(REG) mac_esp_read8(esp, REG)
+#define esp_write8(VAL, REG) mac_esp_write8(esp, VAL, REG)
+
+struct mac_esp_priv {
+ struct esp *esp;
+ void __iomem *pdma_regs;
+ void __iomem *pdma_io;
+};
+static struct esp *esp_chips[2];
+static DEFINE_SPINLOCK(esp_chips_lock);
+
+#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
+ dev_get_drvdata((esp)->dev))
+
+static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
+{
+ nubus_writeb(val, esp->regs + reg * 16);
+}
+
+static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
+{
+ return nubus_readb(esp->regs + reg * 16);
+}
+
+static void mac_esp_reset_dma(struct esp *esp)
+{
+ /* Nothing to do. */
+}
+
+static void mac_esp_dma_drain(struct esp *esp)
+{
+ /* Nothing to do. */
+}
+
+static void mac_esp_dma_invalidate(struct esp *esp)
+{
+ /* Nothing to do. */
+}
+
+static int mac_esp_dma_error(struct esp *esp)
+{
+ return esp->send_cmd_error;
+}
+
+static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
+{
+ int i = 500000;
+
+ do {
+ if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
+ return 0;
+
+ if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+ return 1;
+
+ udelay(2);
+ } while (--i);
+
+ printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
+ esp_read8(ESP_STATUS));
+ esp->send_cmd_error = 1;
+ return 1;
+}
+
+static inline int mac_esp_wait_for_dreq(struct esp *esp)
+{
+ struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
+ int i = 500000;
+
+ do {
+ if (mep->pdma_regs == NULL) {
+ if (via2_scsi_drq_pending())
+ return 0;
+ } else {
+ if (nubus_readl(mep->pdma_regs) & 0x200)
+ return 0;
+ }
+
+ if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+ return 1;
+
+ udelay(2);
+ } while (--i);
+
+ printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
+ esp_read8(ESP_STATUS));
+ esp->send_cmd_error = 1;
+ return 1;
+}
+
+#define MAC_ESP_PDMA_LOOP(operands) \
+ asm volatile ( \
+ " tstw %1 \n" \
+ " jbeq 20f \n" \
+ "1: movew " operands " \n" \
+ "2: movew " operands " \n" \
+ "3: movew " operands " \n" \
+ "4: movew " operands " \n" \
+ "5: movew " operands " \n" \
+ "6: movew " operands " \n" \
+ "7: movew " operands " \n" \
+ "8: movew " operands " \n" \
+ "9: movew " operands " \n" \
+ "10: movew " operands " \n" \
+ "11: movew " operands " \n" \
+ "12: movew " operands " \n" \
+ "13: movew " operands " \n" \
+ "14: movew " operands " \n" \
+ "15: movew " operands " \n" \
+ "16: movew " operands " \n" \
+ " subqw #1,%1 \n" \
+ " jbne 1b \n" \
+ "20: tstw %2 \n" \
+ " jbeq 30f \n" \
+ "21: movew " operands " \n" \
+ " subqw #1,%2 \n" \
+ " jbne 21b \n" \
+ "30: tstw %3 \n" \
+ " jbeq 40f \n" \
+ "31: moveb " operands " \n" \
+ "32: nop \n" \
+ "40: \n" \
+ " \n" \
+ " .section __ex_table,\"a\" \n" \
+ " .align 4 \n" \
+ " .long 1b,40b \n" \
+ " .long 2b,40b \n" \
+ " .long 3b,40b \n" \
+ " .long 4b,40b \n" \
+ " .long 5b,40b \n" \
+ " .long 6b,40b \n" \
+ " .long 7b,40b \n" \
+ " .long 8b,40b \n" \
+ " .long 9b,40b \n" \
+ " .long 10b,40b \n" \
+ " .long 11b,40b \n" \
+ " .long 12b,40b \n" \
+ " .long 13b,40b \n" \
+ " .long 14b,40b \n" \
+ " .long 15b,40b \n" \
+ " .long 16b,40b \n" \
+ " .long 21b,40b \n" \
+ " .long 31b,40b \n" \
+ " .long 32b,40b \n" \
+ " .previous \n" \
+ : "+a" (addr), "+r" (count32), "+r" (count2) \
+ : "g" (count1), "a" (mep->pdma_io))
+
+static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
+ u32 dma_count, int write, u8 cmd)
+{
+ struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
+
+ esp->send_cmd_error = 0;
+
+ if (!write)
+ scsi_esp_cmd(esp, ESP_CMD_FLUSH);
+
+ esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
+ esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
+
+ scsi_esp_cmd(esp, cmd);
+
+ do {
+ unsigned int count32 = esp_count >> 5;
+ unsigned int count2 = (esp_count & 0x1F) >> 1;
+ unsigned int count1 = esp_count & 1;
+ unsigned int start_addr = addr;
+
+ if (mac_esp_wait_for_dreq(esp))
+ break;
+
+ if (write) {
+ MAC_ESP_PDMA_LOOP("%4@,%0@+");
+
+ esp_count -= addr - start_addr;
+ } else {
+ unsigned int n;
+
+ MAC_ESP_PDMA_LOOP("%0@+,%4@");
+
+ if (mac_esp_wait_for_empty_fifo(esp))
+ break;
+
+ n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
+ addr = start_addr + esp_count - n;
+ esp_count = n;
+ }
+ } while (esp_count);
+}
+
+static int mac_esp_irq_pending(struct esp *esp)
+{
+ if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+ return 1;
+ return 0;
+}
+
+static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
+{
+ return dma_len > 0xFFFF ? 0xFFFF : dma_len;
+}
+
+static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
+{
+ int got_intr;
+
+ /*
+ * This is an edge triggered IRQ, so we have to be careful to
+ * avoid missing a transition when it is shared by two ESP devices.
+ */
+
+ do {
+ got_intr = 0;
+ if (esp_chips[0] &&
+ (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
+ (void)scsi_esp_intr(irq, esp_chips[0]);
+ got_intr = 1;
+ }
+ if (esp_chips[1] &&
+ (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
+ (void)scsi_esp_intr(irq, esp_chips[1]);
+ got_intr = 1;
+ }
+ } while (got_intr);
+
+ return IRQ_HANDLED;
+}
+
+static struct esp_driver_ops mac_esp_ops = {
+ .esp_write8 = mac_esp_write8,
+ .esp_read8 = mac_esp_read8,
+ .irq_pending = mac_esp_irq_pending,
+ .dma_length_limit = mac_esp_dma_length_limit,
+ .reset_dma = mac_esp_reset_dma,
+ .dma_drain = mac_esp_dma_drain,
+ .dma_invalidate = mac_esp_dma_invalidate,
+ .send_dma_cmd = mac_esp_send_pdma_cmd,
+ .dma_error = mac_esp_dma_error,
+};
+
+static int esp_mac_probe(struct platform_device *dev)
+{
+ struct scsi_host_template *tpnt = &scsi_esp_template;
+ struct Scsi_Host *host;
+ struct esp *esp;
+ int err;
+ struct mac_esp_priv *mep;
+
+ if (!MACH_IS_MAC)
+ return -ENODEV;
+
+ if (dev->id > 1)
+ return -ENODEV;
+
+ host = scsi_host_alloc(tpnt, sizeof(struct esp));
+
+ err = -ENOMEM;
+ if (!host)
+ goto fail;
+
+ host->max_id = 8;
+ host->dma_boundary = PAGE_SIZE - 1;
+ esp = shost_priv(host);
+
+ esp->host = host;
+ esp->dev = &dev->dev;
+
+ esp->command_block = kzalloc(16, GFP_KERNEL);
+ if (!esp->command_block)
+ goto fail_unlink;
+ esp->command_block_dma = (dma_addr_t)esp->command_block;
+
+ esp->scsi_id = 7;
+ host->this_id = esp->scsi_id;
+ esp->scsi_id_mask = 1 << esp->scsi_id;
+
+ mep = kzalloc(sizeof(struct mac_esp_priv), GFP_KERNEL);
+ if (!mep)
+ goto fail_free_command_block;
+ mep->esp = esp;
+ platform_set_drvdata(dev, mep);
+
+ switch (macintosh_config->scsi_type) {
+ case MAC_SCSI_QUADRA:
+ esp->cfreq = 16500000;
+ esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA;
+ mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
+ mep->pdma_regs = NULL;
+ break;
+ case MAC_SCSI_QUADRA2:
+ esp->cfreq = 25000000;
+ esp->regs = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
+ dev->id * MAC_ESP_REGS_SPACING);
+ mep->pdma_io = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
+ mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
+ dev->id * MAC_ESP_PDMA_REG_SPACING);
+ nubus_writel(0x1d1, mep->pdma_regs);
+ break;
+ case MAC_SCSI_QUADRA3:
+ /* These quadras have a real DMA controller (the PSC) but we
+ * don't know how to drive it so we must use PIO instead.
+ */
+ esp->cfreq = 25000000;
+ esp->regs = (void __iomem *)MAC_ESP_REGS_QUADRA3;
+ mep->pdma_io = NULL;
+ mep->pdma_regs = NULL;
+ break;
+ }
+ esp->fifo_reg = esp->regs + ESP_FDATA * 16;
+
+ esp->ops = &mac_esp_ops;
+ esp->flags = ESP_FLAG_NO_DMA_MAP;
+ if (mep->pdma_io == NULL) {
+ printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
+ esp_write8(0, ESP_TCLOW);
+ esp_write8(0, ESP_TCMED);
+ esp->flags |= ESP_FLAG_DISABLE_SYNC;
+ mac_esp_ops.send_dma_cmd = esp_send_pio_cmd;
+ } else {
+ printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
+ }
+
+ host->irq = IRQ_MAC_SCSI;
+
+ /* The request_irq() call is intended to succeed for the first device
+ * and fail for the second device.
+ */
+ err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
+ spin_lock(&esp_chips_lock);
+ if (err < 0 && esp_chips[!dev->id] == NULL) {
+ spin_unlock(&esp_chips_lock);
+ goto fail_free_priv;
+ }
+ esp_chips[dev->id] = esp;
+ spin_unlock(&esp_chips_lock);
+
+ err = scsi_esp_register(esp);
+ if (err)
+ goto fail_free_irq;
+
+ return 0;
+
+fail_free_irq:
+ spin_lock(&esp_chips_lock);
+ esp_chips[dev->id] = NULL;
+ if (esp_chips[!dev->id] == NULL) {
+ spin_unlock(&esp_chips_lock);
+ free_irq(host->irq, NULL);
+ } else
+ spin_unlock(&esp_chips_lock);
+fail_free_priv:
+ kfree(mep);
+fail_free_command_block:
+ kfree(esp->command_block);
+fail_unlink:
+ scsi_host_put(host);
+fail:
+ return err;
+}
+
+static int esp_mac_remove(struct platform_device *dev)
+{
+ struct mac_esp_priv *mep = platform_get_drvdata(dev);
+ struct esp *esp = mep->esp;
+ unsigned int irq = esp->host->irq;
+
+ scsi_esp_unregister(esp);
+
+ spin_lock(&esp_chips_lock);
+ esp_chips[dev->id] = NULL;
+ if (esp_chips[!dev->id] == NULL) {
+ spin_unlock(&esp_chips_lock);
+ free_irq(irq, NULL);
+ } else
+ spin_unlock(&esp_chips_lock);
+
+ kfree(mep);
+
+ kfree(esp->command_block);
+
+ scsi_host_put(esp->host);
+
+ return 0;
+}
+
+static struct platform_driver esp_mac_driver = {
+ .probe = esp_mac_probe,
+ .remove = esp_mac_remove,
+ .driver = {
+ .name = DRV_MODULE_NAME,
+ },
+};
+module_platform_driver(esp_mac_driver);
+
+MODULE_DESCRIPTION("Mac ESP SCSI driver");
+MODULE_AUTHOR("Finn Thain");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(DRV_VERSION);
+MODULE_ALIAS("platform:" DRV_MODULE_NAME);
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